Gen info
- Etymology: Genus name Histiopteris derives from Greek words histion and pteris, meaning 'webbed fern', referring to the netted veins of the leaves. Specific epithet incisa derives from Latin incidere, meaning 'cut in two', referring to the 'incised leaf'.
- The common name 'bat's wing fern' refers to the lowermost lobes of each pinnae having a bat wing appearance.

Botany
• Terrestrial often summer green fern (deciduous in cooler areas). Rhizomes long-creeping, scaly. Stipe and rachis chestnut-brown at base otherwise mostly yellow-brown (sometimes glaucescent), glabrous except for basal scales, glossy; stipe 0.15-1.2 m long, 5-10 mm diameter. Lamina 0.3-2.3 × 0.15-1.2 m, yellow-green, glaucescent or glaucous (irrespective distinctly glaucous when young), glabrous, ovate, 3-4-pinnate at base. Pinnae sessile, basal pinnules reduced, stipuliform; veins reticulate. Primary pinnae in opposite pairs; longest 130-600 × 70-350 mm, arising at narrow angles, sessile. Secondary pinnae opposite, arising at wide angles; longest 40-200 × 20-90 mm, with basal pair sometimes reduced to stipules. Tertiary pinnae opposite; longest 10-45 × 6-15 mm, sometimes divided into quaternary pinnae. Ultimate pinnules adnate to midribs; margins entire or crenate; apices obtuse. Sori ± continuous around margins, borne on connecting vein, bearing paraphyses; indusia absent, sori protected by reflexed membranous lamina margin. Spores pale, tuberculate. (2)

Distribution
- Native to the Philippines.
- Sprawling over jungles, up to 1500 m altitude.
- Native rang Tropics and Subtropics, growing primarily in the wet tropical biome. (1)

Constituents
- Phytochemical screening of crude extract yielded phenolics, saponins, tannins, and steroids. Phenolic content from 700 m. asl. was 9.8523 mg GAE/g and from 1000 m. asl. was 18.12 g GAE/g(see study below) (4)

Properties
- Studies have suggest antioxidant properties.

Parts used
Leaves.

Uses
Folkloric
- In the Philippines, the Kalanguya tribe of Tinoc, Ifugao apply crushed leaves on burns. (6)
- The Maori of New Zealand apply bruised fronds to indolent ulcers. (7)

Studies
• Antioxidant / Leaves: Antioxidant activity by DPPH assay showed IC50 of 96.42 ppm fo700 m. asl. and 75.63 ppm from 1000 m asl. (see constituents above) (4)
• Ptaquiloside: Ptaquiloside, the sesquiterpenoid carcinogen of Pteridium aquilinum, was isolated from Pteris cretica and Histiopteris incisa. (5)

Availability
Wild-crafted.

Additional Sources and Suggested Readings
(1)
Histiopteris incisa / KEW: Plants of the World Online
(2)
Histiopteris incisa / New Zealand Plant Conservation Network
(3)
Histiopteris incisa / Wikipedia
(4)
Exploration, phenolic content determination, and antioxidant activity of dominant pteridophytes in Gunung Malang Village, Mount Halimun Salak National Park, Indonesia / Vivi Anggia Rindita, Eka Rahmaesa, Retna Kusuma Devi, Lidia Fatmah Alawiyah / BIODIVERSITAS, 2020; 21(8): pp 3676-3682 / eISSN: 2985-4722 / pISSN: 1412-033X / DOI: 10.13057/biodiv/d210834
(5)
The sesquiterpenoid carcinogen of bracken fern, and some analogues, from the pteridaceae / Kimiaki Saito, Takayuki Nagao, Satoshi Takatsuki, Kiyotaka Koyama, Shinsaku Natorii/  Phytochemistry, 1990; 29(5): pp 1475-1479 / DOI: 10.1016/0031-9422(90)80104-O
(6)
Ethnomedical knowledge of plants and healthcare practices among the Kalanguya tribe in Tinoc, Ifugao, Luzon, Philippines / Teodora D Balangcod, Ashlyn Kim D Balangcod / Indian Journal of Traditional Knowledge, 2011; 10(2): pp 227-238
(7)
Histiopteris incisa. Mātātā. Water fern. /  Nga Rauropi Whakaoranga

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